This invention relates generally to dynamo electric machines and, more particularly, to a bonding nib extending from a stator of a dynamo electric machine.
Dynamo electric machines such as an electric motor or generator typically include a housing, a stator, and a rotor assembly. The housing includes a shell having a protective coating and two end shields, and houses at least a portion of the rotor assembly. The stator typically includes a core of magnetic material having an axially extending bore for receiving the rotor assembly. The rotor assembly includes a rotor core and a rotor shaft extending through the core. The rotor assembly extends through the stator opening and the two end shields.
The stator core typically is formed from a plurality of identical laminations coated with an insulating material, aligned, and arranged in a stack held together by clips or an interlock tab. Each lamination includes a plurality of teeth extending radially into the bore. Slots between each of the teeth extend radially outwardly from the bore. The ends of the teeth and the open ends of the slots define the periphery of the bore.
A plurality of coils formed from insulated conductive wire are inserted into selected core slots with portions of the coils at the ends of the core forming end turn regions. The coils are interconnected to form coil groups or poles. The conductive wires which form the coils, are sometimes referred to as stator windings. As an example, a single speed motor typically includes coil groups which establish at least one main winding and an auxiliary or start winding.
The stator is typically interference press fit into the shell of the housing in an attempt to achieve a bond between the stator and the housing shell. Proper bonding between the stator and the housing shell provides adequate grounding of the stator with the housing shell to prevent the stator from arcing. However, as shell coatings and processes have improved to achieve desired corrosion resistance, achieving bond between the coated stator and the coated shell has become more problematic.
Accordingly, it would be desirable to provide a stator that adequately bonds to the housing shell and is durable enough to withstand being interference fit within the shell. In addition, it would be desirable for the stator to be cost effective and to be easy to fabricate.